Close, minimize, and maximize are now close, minimize, and full screen, eliminating the extra full-screen control and consolidating the window controls in one place. Streamlining these and other elements of the interface means you can navigate the desktop more efficiently.

OS X' idea of "maximise" was "some random window resizing nobody really used anyway", so I'm glad Apple finally replaced it with something else. Too bad OS X' fullscreen view is way too disruptive for my tastes to be of any practical use.

The original full screen in lion did indeed make two monitors useless, but this isn't the case anymore. 10.9 allows you to treat monitors as there own desktops and full screen apps one one with out regard of what is on the other.

I personally, use this with remote desktop apps where my secondary monitor is a full screen VM or remote desktop session and I work on my primary in OS X.

Regarding Zoom, I feel it is one of those things you either like or you don't. I'll be honest and admit that I keep TotalSapces and SizeUp installed so I mostly move and re-size windows with my keyboard, but this is true when I use win 7/8 as well.

Monitors are larger now we run them at 1080P to 4k your wasting your realistate to maximize things and I believe zoom was intended to help people realize that. It wasn't intuitive coming from windows, but once I read about the feature I grew to like it and the fact that applications could overwrite the behavior was a feature I liked.

My Email clients and Browsers maximize along with SQL Browsers and large apps, these are normally detailed enough that the interface justifies taking up most of my screen, but text editors, file browsers and other small apps only get large enough to show all the relevant information then I move them in to place.

I have since come to realize this is more efficient then windows and actually helped teach you to multitask. OS X isn't perfect, but what desktop is.